The present invention relates to a rail vehicle body of the type comprising a grid structure, itself having longitudinal elements and cross elements interconnected at nodes, and supporting outer and inner coverings.
In general, the longitudinal and cross elements of grid structures for bodies of the above type are channel-section or xcexa9-section bars.
To assemble the bars together at the nodes of the grid structure, it is generally necessary to cut them.
The nodes of grid structures for bodies of different models are disposed at different locations as a function in particular of the number and positions of windows in the body.
Thus, each new model of vehicle body requires a full new design and new plans.
Furthermore, assembly times and costs associated with such bodies are relatively high, firstly because of the impossibility of making use of automatic bending for the cross bars which need to be curved to match the rounded shape of the body to be obtained, and secondly because of the complexity of assembling the bars together at the nodes of the structure.
An object of the invention is to resolve those problems by providing a rail vehicle body of the above-specified type in which manufacturing time and costs are reduced, and in which the design principle can be reused for bodies of different dimensions and/or shapes, thereby limiting design costs specific to each type of body.
To this end, the invention provides a rail vehicle body of the above-specified type for mounting on a frame, wherein the longitudinal and cross elements of the grid structure are circular section tubes, wherein the grid structure comprises, at at least some of its nodes, connections for interconnecting longitudinal and cross tubes of circular section, wherein these connections have longitudinal and cross sleeves of circular section which receive the longitudinal and cross tubes respectively, and wherein longitudinal tubes pass right through said connections for interconnecting longitudinal and cross tubes.
In particular embodiments the rail vehicle body may include one or more of the following characteristics taken in isolation or in any technically feasible combination:
the grid structure comprises cross hoops mad up of cross tubes of circular section;
each of said cross hoops comprises a curved central tube of circular section located in a roof region of the body, circular section tubes curved more tightly than said central tube and extending said central tube sideways at ends of said central tube in cant-rail regions of the body, and circular section tubes extending the tubes of the cant-rail regions in the side wall regions;
each of said cross hoops has cross tube connections which participate in connecting the central tube of the roof region to the tubes of the side wall regions, and the cross tube connections comprise circular section cross sleeves which receive said tubes of the roof region and of the side wall regions;
said connections of the cross hoops are connections for interconnecting cross tubes and longitudinal tubes, and these connections comprise longitudinal sleeves of circular section which receive longitudinal tubes that pass right through said connections;
the structure comprises welding gussets presenting bearing soleplates towards the outside of the body and on which the outer covering is welded;
welding gussets are carried by circular section tubes of the grid structure;
welding gussets are fixed to circular section tube connections of the grid structure;
the outer covering is connected to the grid structure at least in part by adhesive;
the outer covering is stuck directly to longitudinal elements and/or cross elements of the grid structure; and
the outer covering is fixed to circular section tubes of said structure by resilient engagement.
The invention also provides a rail vehicle having a frame and a body on the frame, wherein said body is a body as defined above.
The invention also provides a method of assembling a body as defined above, wherein, to form said grid structure, longitudinal tubes are inserted in the longitudinal sleeves of said connections for interconnecting longitudinal and cross tubes, said connections are slid to the locations of the nodes of the structure, and said connections are fixed to the longitudinal tubes at said locations.
In particular implementations, the assembly method may include one or more of the following characteristics taken in isolation or in any technically feasible combination:
cross tubes are assembled to the cross sleeves of at least some of said connections for interconnecting longitudinal and cross tubes prior to said connections being fixed at said locations of the nodes of the grid structure;
circular section cross tubes are assembled together to form cross hoops of the grid structure;
to form each of said cross hoops, a curved circular section central tube for placing in a roof region of the body is assembled to circular section tubes that are curved more tightly than said central tube and that are designed to occupy cant-rail regions of the body, and to circular section tubes for extending the tubes of the cant-rail regions into the side wall regions of the body;
for each of said cross hoops, the central tube of the roof region is connected to the tubes of the side wall regions via cross tube connections which have circular section cross sleeves that receive said tubes of the roof region and of the side regions;
said cross hoop connections are connections for interconnecting cross tubes and longitudinal tubes and have longitudinal sleeves of circular section, and in order to form said grid structure, longitudinal tubes are inserted in the longitudinal sleeves of said cross hoop connections, these connections are slid to the locations of the nodes of the structure, and these connections are fixed at said locations;
cross tubes of cross hoops are assembled to the cross sleeves of at least some of said connections for interconnecting longitudinal and cross tubes of the cross hoops before said connections are fixed at said locations of the nodes of the grid structure;
welding gussets are fixed to the grid structure with bearing soleplates of said gussets being directed towards the outside of the body, and then the outer covering of the body is welded to said soleplates;
welding gussets are fixed to the tube connections of the grid structure;
the outer covering is secured to the grid structure at least in part by means of adhesive;
the outer covering is stuck directly to longitudinal and/or cross elements of the grid structure; and
the inner covering is assembled to the grid structure by resilient engagement on circular section tubes of said structure.
The invention also provides a method of assembling a vehicle as defined above, wherein the grid structure of the vehicle body is assembled using a method as defined above.